Xenii
.
- Joined
- Feb 16, 2024
- Messages
- 125
- Likes
- 442
- Location
- Switzerland
- Portables
- Xii-Boy Original, Xii-Boy Pocket, Xii-Boy Ultra
Hi there!
A few months ago, I released a GitHub repository containing the Matterhorn 64 Core files and instructions, but I completely forgot to make a post which talks about it here.
I guess it's time to fix that!
Preface
Matterhorn 64 CORE is the world's smallest open-source Nintendo 64 motherboard redesign.
It features all the main components from the original console in a small and compact form factor.
Since the design relies on the original chips, all the games run as well as they used to. No emulation is used.
This board has been design for my futures projects such as Matterhorn 64 and Weisshorn 64.
Story
During the Xii-Boy Ultra development (beginning of 2025), I had the idea of making a really cool Nintendo 64 portable.
I really wanted to make a portable that is super simple; A single motherboard, a few buttons and a screen.
My goal was simple: Create an All-In-One motherboard, 100% wirefree.
Designing such a thing needed something pretty difficult to accomplish though; a redesigned N64 motherboard.
After some research, I discovered that a few people out there have tried doing a similar project.
- @marshallh made a working one back in 2016
- @Gman also made a working one back in 2020
- @SparkleBear tried in 2022
- @thedrew also tried in 2024
All of them represented a huge source of inspiration. Unfortunately, none of them were open source.
@cy's awesome contribution with his motherboard recreation called OpeN64 was not released at that time.
Therefore, I decided to create my own in order to fulfill my needs for my Nintendo 64 portable project.
I was pretty busy with the Xii-Boy Ultra Beta Kits, thus I didn't have a lot of time to work on the design. I actually started designing the board in October 2025, during my school holidays.
The board took a few months to design. I actually finished it in late January 2026.
I ordered the board through JLCPCB and a few days later, they arrived at my home in Switzerland!
Design
Here is a few pictures of the finished design, the one currently available on the GitHub repository.
Schematic:
PCB (3D renders)
PCB (L1 to L4)
Cartridge Breakout Board (3D render)
Size comparison with an original console
Assembly and Tests
As soon as I received the boards, I took apart Nintendo 64 console and removed the main chips using my hot air station.
Huge thanks to my friend ModdingMarius who really generously sold me some Nintendo 64 with broken shells, which were perfect for the project.
Definitively check what he does, his content rocks!
After a weekend of soldering 0402 passives, the board assembly was complete, the test was ready to begin
I want to thank @cy who was super kind and offered me to test the board by being in call, it was a fun time!
Unfortunately, I had some issues with the power supply, and the board refused to boot properly.
After some tweaks, and by changing the power supply, the board finally booted!
A little Youtube video can be found here:
The core runs successfully my copy of Ocarina of Time in PAL version
Features
The Matterhorn 64 CORE:
The link to the repository can be found here!
Matterhorn 64 CORE GitHub Repository
All the files can be found there, as long as all the technical information needed to order and assemble your own.
Future Projects
As I stated, the Matterhorn 64 CORE will be used in my ultimate Nintendo 64 Portable, the worklog can be found here: Matterhorn 64 Worklog
It will also be used in the Weisshorn 64 project, which is the project I am currently working on. It does not have a dedicated worklog yet, I will put the link here as soon as I finish writing its first episode. Weisshorn 64 will be the smallest Nintendo 64 console, a kind of Nintendo 64 Classic Mini that we never got from Nintendo. More details will follow soon!
Credits
Since this project is the most complicated I've done so far, I wanted to properly thank the ones who helped throughout my journey!
Therefore, big thanks to:
Thanks a lot, have a nice day and see you next time!
A few months ago, I released a GitHub repository containing the Matterhorn 64 Core files and instructions, but I completely forgot to make a post which talks about it here.
I guess it's time to fix that!
Preface
Matterhorn 64 CORE is the world's smallest open-source Nintendo 64 motherboard redesign.
It features all the main components from the original console in a small and compact form factor.
Since the design relies on the original chips, all the games run as well as they used to. No emulation is used.
This board has been design for my futures projects such as Matterhorn 64 and Weisshorn 64.
Story
During the Xii-Boy Ultra development (beginning of 2025), I had the idea of making a really cool Nintendo 64 portable.
I really wanted to make a portable that is super simple; A single motherboard, a few buttons and a screen.
My goal was simple: Create an All-In-One motherboard, 100% wirefree.
Designing such a thing needed something pretty difficult to accomplish though; a redesigned N64 motherboard.
After some research, I discovered that a few people out there have tried doing a similar project.
- @marshallh made a working one back in 2016
- @Gman also made a working one back in 2020
- @SparkleBear tried in 2022
- @thedrew also tried in 2024
All of them represented a huge source of inspiration. Unfortunately, none of them were open source.
@cy's awesome contribution with his motherboard recreation called OpeN64 was not released at that time.
Therefore, I decided to create my own in order to fulfill my needs for my Nintendo 64 portable project.
I was pretty busy with the Xii-Boy Ultra Beta Kits, thus I didn't have a lot of time to work on the design. I actually started designing the board in October 2025, during my school holidays.
The board took a few months to design. I actually finished it in late January 2026.
I ordered the board through JLCPCB and a few days later, they arrived at my home in Switzerland!
Design
Here is a few pictures of the finished design, the one currently available on the GitHub repository.
Schematic:
PCB (3D renders)
PCB (L1 to L4)
Cartridge Breakout Board (3D render)
Size comparison with an original console
Assembly and Tests
As soon as I received the boards, I took apart Nintendo 64 console and removed the main chips using my hot air station.
Huge thanks to my friend ModdingMarius who really generously sold me some Nintendo 64 with broken shells, which were perfect for the project.
Definitively check what he does, his content rocks!
After a weekend of soldering 0402 passives, the board assembly was complete, the test was ready to begin
I want to thank @cy who was super kind and offered me to test the board by being in call, it was a fun time!
Unfortunately, I had some issues with the power supply, and the board refused to boot properly.
After some tweaks, and by changing the power supply, the board finally booted!
A little Youtube video can be found here:
The core runs successfully my copy of Ocarina of Time in PAL version
Features
The Matterhorn 64 CORE:
- Is the world's smallest open source Nintendo 64 motherboard recreation
- Fits in a tiny 78x77.2mm form factor
- Runs on real hardware and real chips, no emulation
- 100% with all the game released on the system (even flashcard such as the SummerCart 64)
- Compatible with both NTSC and PAL motherboards (a corresponding jumper must be bridged to set the region)
- Runs on 3.3V and draws a bit less than 2A
- Designed using KiCad 9
- Clean routing and proper 4-layer implementation and impedance matching
- 100% open source, can be used anywhere for anything
- Released under the CERN-OHL-S-2.0 license
The link to the repository can be found here!
Matterhorn 64 CORE GitHub Repository
All the files can be found there, as long as all the technical information needed to order and assemble your own.
Future Projects
As I stated, the Matterhorn 64 CORE will be used in my ultimate Nintendo 64 Portable, the worklog can be found here: Matterhorn 64 Worklog
It will also be used in the Weisshorn 64 project, which is the project I am currently working on. It does not have a dedicated worklog yet, I will put the link here as soon as I finish writing its first episode. Weisshorn 64 will be the smallest Nintendo 64 console, a kind of Nintendo 64 Classic Mini that we never got from Nintendo. More details will follow soon!
Credits
Since this project is the most complicated I've done so far, I wanted to properly thank the ones who helped throughout my journey!
Therefore, big thanks to:
- @cy for contributed some files for the project such as footprint and also took some time to test the board with me
- @CrazyGadget who designed great open-source flexes which helped me to understand some part of the motherboard
- @YveltalGriffin who answered all my technical questions and also took the time to review the board in depth!
- @marshallh, @Gman, @SparkleBear and @thedrew who gave me the inspiration to design my own 3x3 redesign
Thanks a lot, have a nice day and see you next time!
